I took Sabotloaders advice and tightened up the BP on the ACCURA a little more than I usually do, kinda tight with Teflon Tape on it. I also put a rubber O-Ring under the Primer. This made a Big difference. Blow Back was minimal and only on the firing pin face area, one little wipe and it was clean. So for now Im going with this was and I wont have to adjust for elevation if I modify the BP with a vent liner.
(BP)